Based on the requirements from the bug #220213 [ Add Property behavior is not smooth], there's a need for being able to put a custom UI component to the place where property names are normally rendered.
In particular we need to add the "Add Property" JComboBox to the last line and first column of the property sheet when it shows css rule properties. Once user selects a property name the focus is moved to the value field and the editing continues there. Having this would improve the flow as now the place where user specifies the values jumps from the bottom of the RE panel to the property sheet.
blocked by #220256 - Support for double-click to a FeatureDescriptor
(In reply to comment #1)
> blocked by #220256 - Support for double-click to a FeatureDescriptor
please disregard this, should come to different issue